Apparatus for applying two-part surgical fasteners

ABSTRACT

In apparatus for applying a two-part surgical fastener including a fastener part having at least one prong and a retainer part having an aperture for receiving and retaining the distal end of the prong, the retainer part is initially held securely to the apparatus by contact with a lug extending into the aperture. When the two parts of the fastener are forced together, the distal end of the prong pushes the lug out of the aperture, thereby releasing the retainer part from the apparatus.

BACKGROUND OF THE INVENTION

This invention relates to surgical fastening apparatus, and moreparticularly to apparatus for applying surgical fasteners comprising twointerlocking parts.

Surgical fasteners have been developed which comprise a fastener parthaving one or more prongs and a retainer part having a correspondingnumber of apertures for respectively receiving and engaging the ends ofthe prongs of the fastener part (see, for example, Noiles U.S. Pat. No.4,060,089). Both parts of the fastener are typically made of a plasticor plastic-like material which may be biologically absorbable. In use,the fastener and retainer parts are respectively positioned on oppositesides of the tissue to be fastened. The fastener part is then driventoward the tissue so that the prongs pass through the tissue andinterlock with the retainer part. The retainer part prevents the prongsfrom being withdrawn from the tissue.

In applying surgical fasteners of this type it is important for theretainer part to be held securely prior to engaging the fastener part.This is required to prevent the retainer part from becoming loose andpossibly lost in the operating site and to assure that each fastenerpart mates with a retainer part to provide the intended surgicalfastening. Once the fastener and retainer parts have interlocked,however, it is equally important for the structure which supports theretainer part to readily release the retainer part so that the fastenedtissue can be easily removed from the fastener applying apparatus.

In view of the foregoing, it is an object of this invention to improveand simplify apparatus for applying two-part surgical fasteners of thetype described above.

It is a more particular object of this invention to provide apparatusfor applying two-part surgical fasteners of the type described above inwhich the retainer part is held firmly in the apparatus until the twoparts of the fastener are joined, after which the retainer parts arereleased from the apparatus.

SUMMARY OF THE INVENTION

These and other objects of the invention are accomplished in accordancewith the principles of the invention by providing a support structurefor the retainer part of a two-part surgical fastener, the supportstructure including means for releasably engaging the retainer partuntil the prong or prongs of the fastener part have interlocked with theretainer part, at which time the prong or prongs contact the means forreleasably engaging the retainer part and cause that means to releasethe retainer part.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawing and the followingdetailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1a is a perspective view of an illustrative embodiment of surgicalfastener applying apparatus constructed in accordance with thisinvention. FIG. 1a shows the permanent actuator and disposable cartridgeof this apparatus separate from one another.

FIG. 1b is similar to FIG. 1a but shows the cartridge mounted in theactuator and the apparatus in use.

FIG. 2 is an enlarged view of the cartridge portion of the apparatusshown in FIG. 1b with portions cut away to reveal the interiorcomponents.

FIG. 3 is a sectional view taken along the line 3--3 in FIG. 2.

FIG. 4 is a view similar to FIG. 2 but showing the apparatus after thetwo parts of the fasteners have been joined.

FIG. 5 is a sectional view taken along the line 5--5 in FIG. 4.

FIG. 6 is an enlarged elevational view of a portion of the apparatus ofFIGS. 1-5.

FIG. 7 is a sectional view taken along the line 7--7 in FIG. 6.

FIG. 8 is a view similar to FIG. 7 but showing the apparatus after thetwo parts of the fasteners have been joined.

FIG. 9 is a sectional view taken along the line 9--9 in FIG. 8.

FIG. 10 is a perspective, exploded view of a portion of the apparatus ofFIGS. 1-9.

DETAILED DESCRIPTION OF THE INVENTION

The surgical fastener applying apparatus shown in the accompanyingdrawing is only one possible environment of the present invention. Asshown in FIG. 1a, this apparatus includes reusable actuator 10 and areplaceable and disposable fastener-carrying cartridge 30. Although notnecessary to an understanding of the present invention, full detailsregarding the construction and operation of actuator 10 are provided incommonly assigned, co-pending Green U.S. patent application Ser. No.267,080, filed May 26, 1981 now U.S. Pat. No. 4,383,634. Similarly,additional details regarding the construction and operation of afastener-carrying cartridge similar to cartridge 30 are provided inGreen U.S. Pat. No. 4,354,628.

Actuator 10 includes proximal handle 12, distal cartridge holder 14, andintermediate shaft assembly 16. Cartridge 30 includes proximalfastener-holding assembly 32 and distal retainer-holding assembly 34.Assemblies 32 and 34 are pivotally connected to one another by pivotalconnection 36. Cartridge 30 slides into actuator 10 as shown in FIG. 1bwith retainer-holding assembly 34 firmly but releasably engaged in thedistal leg of cartridge holder 14 and with fastener-holding assembly 32freely movable on pivotal connection 36 between the parallel spacedsides of the proximal leg of cartridge holder 14.

Tissue 18 to be fastened is positioned between fastener-holding assembly32 and retainer-holding assembly 34. Clamp actuator 20 on actuator 10 ispivoted parallel to shaft assembly 16. This causes clamping assembly 22to translate toward fastener-holding assembly 32, thereby pivoting thefastener-holding assembly into parallel relationship withretainer-holding assembly 34. As clamping assembly 22 translates towardfastener-holding assembly 32, it first contacts leaf spring 38 which isfixedly mounted near the bottom of fastener-holding assembly 32 andwhich projects proximally outward from the proximal side of assembly 32.The upper end of leaf spring 38 engages alignment pin 40. When clampingassembly 22 contacts leaf spring 38 as described above, it both pivotsassembly 32 toward assembly 34 and substantially flattens leaf spring 38against the proximal side of assembly 32. This drives alignment pin 40in the distal direction so that the distal end of pin 40 projects out ofassembly 32 and into aperture 42 near the top of assembly 34. This helpsto align assemblies 32 and 34 during application of the fasteners to thetissue.

When the tissue 18 has been clamped in the apparatus as described above,fastener actuator 24 is squeezed toward handle 12. This causes elementsin assemblies 20 and 22 (the distal-most of these elements being rod 26,FIGS. 2 and 3) to translate in the distal direction. Rod 26 enters theproximal side of fastener-holding assembly 32 as shown in FIGS. 4 and 5and drives fastener pushers 50 in the distal direction. Each of fastenerpushers 50 pushes a U-shaped surgical fastener part 60 in the distaldirection. As best seen in FIG. 8, each fastener part 60 includes a base62 and two parallel prongs 64, each prong being perpendicular to thebase at a respective one of the opposite ends of the base.

When fastener parts 60 are thus driven in the distal direction, prongs64 pass through the clamped tissue. After passing through the tissue,the distal end of each prong enters an aligned aperture 82 in a retainerpart 80 associated with the fastener part. Retainer parts 80 aresupported by and releasably retained in retainer-holding assembly 34 aswill be described in greater detail below. As best seen in FIG. 9, thedistal end of each prong 64 has an enlarged head 66 which interlockswith interior surfaces 84 of the retainer member aperture to preventprongs 64 from being withdrawn from the retainer member apertures afterthe two parts of the fastener have been forced together. Each retainerpart 80 thus prevents the associated fastener part 60 from pulling outof the tissue. Fastener part 60 and retainer part 80 cooperate to applypressure to the fastened tissue as is necessary for such purposes astissue approximation and hemostasis. In the particular embodiment shownin the drawing, the apparatus applies two parallel rows of fasteners,the rows being longitudinally offset from one another.

When the fasteners have been applied to the tissue as described above,fastener actuator 24 is released. This retracts pin 26 fromfastener-holding assembly 32. Clamp actuator 20 is then pivoted out toits original position by depressing release 28. The outward pivoting ofclamp actuator 20 retracts clamping assembly 22 and allows cartridge 30to pivot open. The fastened tissue is removed from cartridge 30. Theapparatus is readied for reuse by removing and discarding expendedcartridge 30 and reloading actuator 10 with a new cartridge. Betweensurgical procedures actuator 10 must be cleaned and sterilized, but nosuch cleaning and sterilization is required for disposable cartridges30.

Before surgical fasteners 60, 80 are applied to the tissue as describedabove, retainer parts 80 are held on retainer-holding assembly 34 bydeformable holder members or lugs 44 (FIGS. 6 and 7) which project intothe distal side of retainer part apertures 82. In their initial or firstpositions, lugs 44 fit tightly into apertures 82 so that retainer parts80 are held securely on retainer-holding assembly 34 by the frictionalfit between lugs 44 and the retainer parts. Like retainer parts 80, lugs44 and the adjacent nondeformable supporting structure are preferablymade of a plastic or plastic-like material. Most preferably, lugs 44 andthe adjacent nondeformable supporting structure are integral.

Each lug 44 projects far enough into the associated retainer partaperture 82 so that, when the associated fastener prong 64 entersaperture 82, the distal end of the prong contacts the lug and deflectsor deforms it to a second position as shown in FIGS. 8 and 9. In theembodiment shown in FIGS. 6-10, each lug 44 is basically a block whichis connected along only one edge 46 to the nondeformable body ofretainer-holding assembly 34. The other edges of each lug 44 areunsupported. Thus when the distal end of the associated prong 64contacts each lug 44, the edge 46 of the lug by which it is connected tothe body of retainer-holding assembly 34 acts as a deformable flexuralhinge having a pivotal axis substantially perpendicular to thelongitudinal axis of prong 64. Each lug 44 pivots about this hinge 46when contacted by the distal end of the associated prong 64. Prongs 64force lugs 44 substantially out of apertures 82, thereby breaking thefrictional contact between lugs 44 and retainer parts 80. This releasesretainer parts 80 from retainer-holding assembly 34 so that the fastenedtissue is easily removed from the apparatus. Lugs 44 remain connected tothe body of retainer-holding assembly 34 by hinges 46.

As mentioned above, two-part surgical fasteners of the type describedherein are usually made of a plastic or plastic-like material. Suchmaterial may be preferred because it does not scatter X-rays the waymetal surgical staples do. In some applications, however, it may not bepossible for plastic prongs 64 to penetrate the tissue to be fastenedunaided. If that is the case, metal piercers or guides may be providedin fastener-holder assembly 32 as shown, for example, incommonly-assigned, co-pending Green U.S. patent application Ser. No.310,065, filed Oct. 9, 1981. In general, one such metal piercer isprovided adjacent each prong. The sharp distal end of each piercerpasses through the tissue just ahead of the distal end of the associatedprong. If such piercers are used with the apparatus of the presentinvention, it will be apparent that the distal ends of the piercersrather than the distal ends of the fastener prongs may contact lugs 44and deflect those lugs out of retainer part apertures 82. It willtherefore be understood that the term "prong" as used herein and in theappended claims includes both the actual fastener part prong 64 and/orany associated metal piercer. This definition of the term "prong"applies even though the metal piercers may be withdrawn from proximityto the fasteners after the fastening has been completed.

When, as in the embodiment depicted in the accompanying drawing,multiple fasteners are driven simultaneously, especially without metalpiercers or guides, it has been found desirable to connect pushers 50rigidly together in a plurality of small groups which are mutuallyexclusive and collectively exhaustive of the totality of pushers. In theparticularly preferred embodiment shown in FIG. 10, three pushers 50 areformed integrally on each pusher mounting 52. All of pusher mountings 52are driven simultaneously by channel member 56 which is looselyassociated with pusher mountings 52 so that channel member 56 does notconstitute a rigid connection between pusher mountings 52. If eachpusher 50 were separate, the pushers might have a tendency to becomemisaligned and therefore bind in their respective pusher channels 58. Onthe other hand, if all the pushers 50 were integral, any cocking of thepusher structure might again cause the pusher structure to bind relativeto pusher channels 58. It has been found that joining pushers 50together in small groups is preferable to either of the two extremesmentioned above. In particular, the integral structure of three pushersshown in FIG. 10 has been found especially desirable. This structureconsists of two adjacent pushers 50 in one row of fasteners and oneintermediate pusher 50 in the adjacent row of fasteners. The two pusherstructures 52a and 52b adjacent to pusher structure 52 (portions ofwhich are visible in FIG. 2) are identical but reversed (i.e., with twopushers 50 in the row of fasteners having only one pusher 50 in fullydepicted pusher structure 52). Providing three pushers integrally inthis manner helps to stabilize the individual pushers withoutintroducing into the apparatus a long, rigid structure which might tendto bind even if slightly cocked.

It will be understood that the foregoing is merely illustrative of theprinciples of the invention, and that various modifications can be madeby those skilled in the art without departing from the scope and spiritof the invention. For example, metal piercers can be provided to assistthe fastener prongs in passing through the tissue if desired. As anotherexample of modifications within the scope of the invention, actuator 10and cartridge 30 could be made as one integral disposable unit.

I claim:
 1. An apparatus for applying a surgical fastener made up of twointerlocking parts comprising:a fastener including a fastener parthaving a prong which passes through the tissue to be fastened and aretainer part for interlocking with the end of the prong after it haspassed through the tissue to prevent the prong from being subsequentlywithdrawn from the tissue; and a structure for releasably supporting theretainer part prior to interlocking of the prong and the retainer part,the supporting structure including a deformable part for releasablyengaging the retainer part, the deformable part being contacted anddeformed by the prong as the prong interlocks with the retainer part,and the deformable part responding to such deformation by releasing theretainer part.
 2. The apparatus defined in claim 1 wherein thedeformable part engages the retainer part by frictional contact betweenthe deformable part and the retainer part.
 3. The apparatus defined inclaim 1 wherein the retainer part includes an aperture extending throughthe retainer part substantially parallel to the longitudinal axis of theprong, wherein, prior to deformation, the deformable part extends intothe aperture from the side of the retainer part which faces away fromthe prong, and wherein the prong enters the aperture in order tointerlock with the retainer member and to substantially displace thedeformable part from the aperture.
 4. The apparatus defined in claim 3wherein the supporting structure further includes a retainer backup partadjacent the side of the retainer part which faces away from the prong,and wherein the deformable part comprises:a lug which, prior todeformation, extends into the aperture from the side of the retainerpart which faces away from the prong; and a hinge connection between oneside of the lug and the retainer backup part.
 5. The apparatus definedin claim 4 wherein the pivotal axis of the hinge connection issubstantially perpendicular to the longitudinal axis of the prong. 6.The apparatus defined in claim 4 wherein the lug is unsupported relativeto the retainer backup part except for the hinge connection.
 7. Theapparatus defined in claim 4 wherein the retainer backup part, the lug,and the hinge connection are integral, and wherein the hinge connectionis a flexural hinge.
 8. An apparatus for applying a surgical fastenercomprising:a fastener member located on one side of the tissue to befastened and having a prong which passes through the tissue to befastened; a retainer member located on the other side of the tissue tobe fastened and having an aperture for receiving and retaining the endof the prong after it has passed through the tissue to prevent the prongfrom being subsequently withdrawn from the tissue; a structure adjacentthe side of the retainer member which faces away from the tissue to befastened for supporting the retainer member against the tissue prior toand during insertion of the prong in the aperture; a holder member forreleasably engaging the retainer member and holding the retainer memberagainst the supporting structure prior to insertion of the prong in theaperture; a deformable connection for connecting the holder member tothe supporting structure; and means responsive to the insertion of theprong in the aperture for deforming the deformable connection so thatthe holder member moves out of engagement with the retainer member andpermits the retainer member to move away from the supporting structure.9. The apparatus defined in claim 8 wherein the holder member engagesthe retainer member by frictional contact with the retainer member. 10.The apparatus defined in claim 8 wherein the holder member is disposedin a portion of the retainer member aperture while engaging the retainermember, and wherein the prong forces the holder member out of theretainer member aperture when the prong enters the aperture.
 11. Theapparatus defined in claim 10 wherein the deformable connection is ahinge connection between one side of the holder member and thesupporting structure.
 12. The apparatus defined in claim 11 wherein thepivotal axis of the hinge connection is substantially perpendicular tothe longitudinal axis of the prong.
 13. The apparatus defined in claim11 wherein the holder member is unsupported relative to the supportingstructure except for the hinge connection.
 14. The apparatus defined inclaim 11 wherein the supporting structure, the holder member, and thehinge connection are integral, and wherein the hinge connection is aflexural hinge.
 15. An apparatus for applying a surgical fastener madeup of two interlocking parts comprising:a fastener including a fastenerpart having a prong which passes through the tissue to be fastened and aretainer part for interlocking with the end of the prong after it haspassed through the tissue to prevent the prong from being subsequentlywithdrawn from the tissue; a first member for supporting the retainerpart prior to interlocking of the prong and the retainer part; and asecond member connected to the first member and movable between a firstposition in which the second member engages the retainer part to securethe retainer part to the first member, and a second position in whichthe second member releases the retainer part so that the retainer partis no longer secured to the first member, the second member beingcontacted and moved from the first position to the second position bythe prong as the prong interlocks with the retainer part.
 16. Theapparatus defined in claim 15 wherein the retainer part includes anaperture extending through the retainer part substantially parallel tothe longitudinal axis of the prong, wherein in the first position thesecond member extends into the aperture from the side of the retainerpart which faces away from the prong, and wherein the prong enters theaperture in order to interlock with the retainer member and tosubstantially displace the second member from the aperture whichcorresponds to the second position of the prong.
 17. The apparatusdefined in claim 16 wherein the second member engages the retainer partby frictional contact with interior surfaces of the aperture.
 18. Theapparatus defined in claim 17 wherein the second member is pivotallyconnected to the first member by a hinge connection along a first sideof the second member, the pivotal axis of the hinge connection beingsubstantially perpendicular to the longitudinal axis of the prong. 19.The apparatus defined in claim 18 wherein the first member, the secondmember, and the hinge connection are integral.
 20. The apparatus definedin claim 19 wherein the hinge connection is a flexural hinge. 21.Apparatus for simultaneously driving a plurality of surgical fastenersfrom a fastener-holding assembly, each fastener including a longitudinalbase substantially parallel to the surface of the tissue to be fastenedand two prongs substantially perpendicular to the surface of the tissueto be fastened, each prong being attached to the base adjacent arespective one of the ends of the base, the fasteners being disposed intwo parallel rows which are longitudinally offset from one another, theapparatus comprising:a plurality of fastener pushers disposed in afastener-holding assembly, each pusher being substantially perpendicularto the surface of the tissue to be fastened and each pusher acting onthe base of a respective one of the fasteners to drive the associatedfastener from the fastener-holding assembly; pusher mounting means forrigidly connecting adjacent pushers together in a plurality of groupswhich are mutually exclusive and collectively exhaustive of the totalityof pushers, each group of pushers consisting of two pushers respectivelyassociated with two adjacent fasteners in one of the rows and one pusherassociated with the intermediate fastener in the other row; means forsimultaneously pushing all of the groups of pushers toward the fastenersto drive the fasteners from the fastener-holding assembly; and eachpusher mounting means being located adjacent another pusher mountingmeans and having recessed shoulder portions retaining the rows ofpushers in alignment without forming a rigid connection between any ofsaid groups.